Vibronic sensors are widely applied in process and/or automation technology. In the case of fill-level measuring devices, they comprise at least one mechanically oscillatable unit, such as, for example, an oscillatory fork, single rod or membrane. Such is excited during operation by means of a driving/receiving unit, frequently in the form of an electromechanical transducer unit, to execute mechanical oscillations. The electromechanical transducer unit can be, for example, a piezoelectric drive or an electromagnetic drive. The mechanically oscillatable unit can, in the case of flow measuring devices, however, also be embodied as an oscillatable tube, through which the medium flows, such as, for example, in a measuring device working according to the Coriolis principle.